FR2598652A1 - MULTI-MATERIAL SIMULTANEOUS EXTRUSION MACHINE - Google Patents

Abstract

SUCH A MACHINE IS ESPECIALLY SUITABLE FOR COATING A PROFILE INSERT AND IS OUTSTANDING IN THE FACT THAT IT IS MADE UP OF SEVERAL CORDLING SCREWS 1, 2, 3 INCORPORATED IN THE SAME BLOCK 4, SUPPLIED EACH FROM A HOPPER. , THROUGH A RESPECTIVE ORIFICE 1, 2, 3, IN A CONNECTION HEAD 5 HAVING A PIPING 6, 7, 8 FOR EACH MATERIAL BULBED AND HOLLOWWAY AXISED FOR THE PASSAGE OF AN INSERT, THIS CONNECTION HEAD 5 BY THE INTERMEDIATE OF A PERFORATED DISTRIBUTOR RING 9 AND GROOVE CONCENTRICALLY FOLLOWING THE PIPES OF THE LATTER, AN EXTRUSION ENCLOSURE 10 WITH CONTROLLED VEINS, BRINGING OUT AN EXTRUSION HEAD WITH PASSAGE RESERVED FOR THE INSERT, CONTAINING A FURNACE TRONCONIQUE 12 LOGEANT, FROM ITS ENTRY TO ITS EXIT, A DIFFUSER 13 EXTERIOR RIBS, IN WHICH EACH GROOVE BETWEEN TWO RIBS CORRESPONDING TO A PORT OF THE EXTRUSION ENCLOSURE 10, A TRONCONIC CORE RIB AND EXTERNAL GROOVE ANIERE THAT ITS RIBS AND GROOVES CORRESPOND TO THOSE OF THE DIFFUSER 13, A HOLLOW-THROUGH INTERIOREMNET CONICAL IN CORRESPONDENCE WITH THE CONICITY OF THE RIBS AND RADIAL GROOVES OF THE CORE, THIS ARRANGEMENT INCLUDING A CUT-OUT OF THE PROFILE.

Description

1 2598652

  The present invention relates to a machine for the simultaneous extrusion of several materials and, more particularly, it relates to such a compact manufacturing machine, allowing the continuous coating of an insert in the form of a profile, or the continuous extrusion of 'a profile of complex form, by means of the various materials extruded simultaneously by the extruders arranged in juxtaposition relative to each other. In the technique of extruding thermoplastics or elastomeric products, for example, extrusion plants are currently used which group together several extruders arranged in

  T or Y and connected to a common extrusion head carrying the die.

  These installations are not only large in size and therefore occupy a large space, but are complicated to produce, both with regard to the common extrusion head which is heavy and complex, as well as relates to the sector itself. On the other hand, when using such an installation, for example for the extrusion of a bielastomer, trielastomer or reinforced plastomer profile, the extruders are often under-used and it is necessary to reduce the speed of

  rotation of the extruder screws, which increases the internal leakage and is detrimental to the quality of the extruded profile.

  In order to avoid the major part of the disadvantages presented by these known installations, the inventor designed an extrusion machine of greatly reduced model compared to these installations and having a

  equivalent yield, if not higher than these.

  According to the invention, such an extrusion machine is constituted by several extruding screws incorporated in the same block, each supplied from a particular hopper and opening, through a respective orifice, into a connection head having a particular channel for each beaded material and axially hollowed out for the passage of an insert, this connecting head supplying, via a perforated and grooved distributor ring concentrically along the pipes of the latter, an extrusion chamber with controlled veins known in the technique, carrying at its outlet an extrusion head with a passage reserved for the insert, if the latter is to be embedded in the extruded profile, this extrusion head consisting of a frustoconical lining or envelope accommodating, from its entry to its exit, a frustoconical diffuser ribbed radially externally, in which each groove between two radial ribs corresponds to an orifice of the enclosure extrusion, a radially outer ribbed and grooved frusto-conical core 40 so that its ribs and grooves correspond to those of the diffuser, a frustoconical die hollowed out internally in a conical manner in correspondence with the conicity of the radial ribs and grooves

  of the core, this die obviously comprising a passage cut to the shape of the desired profile.

  More specifically and according to the invention, the extruding screws are housed in bores of the block parallel to each other and juxtaposed, this block being provided with internal pipes surrounding these screws in the manner of a radiator and circulating the water and the steam from

  hydraulic motors for rotating these screws.

  Furthermore, the connection head forms a body with the block of extruders and houses a frustoconical core axially bored to provide the passage for the insert and provided with external grooves of substantially helical shape, opening through segmental annular orifices against the distributor ring, in number equal to that of the screws 15 and each originating at the level of the exit orifice of a extruder. Note that this frustoconical core is fixed, has a base in which the annular orifices are made, at the outlet of the external grooves, according to different diameters to avoid any connection

  between them, has a threaded top for screwing its fixing nut into the block and is positioned normal to extruders in line.

  On the other hand, the distributor ring is in the form of a cylindrical ring, of the same diameter as that of the base of the core of the connecting head, axially bored by an insert passage orifice in correspondence with that of this core and provided, on its face adjacent to it, with annular grooves provided with the same diameters as those of the segmental annular orifices of the base of this core, these annular grooves being provided with biased perforations opening into orifices provided in the opposite face of this ring in correspondence with the admission orifices of the enclosure with controlled veins. Note that this enclosure, known in extrusion techniques, is described, among other things, in European patent No. 0 031 742. Furthermore, the biased perforations in the annular grooves of the dispensing ring are milled to accept spikes. obturation as a function of annular grooves used in the distribution of the extruded materials, these grooves being themselves designed to receive material retainers distributed according to the delimitation of the groove segments chosen for feeding

  enclosure inlet ports.

  As far as it is concerned and as defined above, the extrusion head incorporating the die and arranged at the outlet of this enclosure consists of a frustoconical envelope incorporating a

3 2598652

  frusto-conical diffuser ribbed and grooved radially, a frusto-conical ribbed and grooved core also radially in correspondence with the diffuser and a conically hollow die in which the ribs of the core abut. The frustoconical envelope is adapted to be housed in the fixing flange of the extrusion head and is conically bored convergently towards its outlet to maintain the stacking of the diffuser, of the core and of the die, as well as a sealing ring placed at the rear of the diffuser and having a bore corresponding to the circumscribed circle

  orifices of the extrusion enclosure, the rear face of this ring being pressed against the front or exit face of this enclosure.

  For its part, the frustoconical diffuser is formed in a single block where the radial ribs, of frustoconical external shape with converging conicity, form grooves between them, the bottom of which is with diverging conicity in the direction of their exit, the bottoms at the entrance being curved lower than the diameter of the inscribed circle of the outlet orifices of the extrusion enclosure with controlled veins and these bottoms, on the outlet side, corresponding to the outside diameter of the frustoconical core. Note that one of the ribs of this diffuser is thicker than the others

  and has an internal air intake channel.

  Furthermore, this frustoconical core also consists of a single block o the radial ribs and the bottom of the grooves has a converging taper towards their exit from the side of the die, this bottom of each groove being rounded so that a single generator touches the bottom of the chain. As far as it is concerned, the wall of this die is hollowed conically in correspondence with the taper of the radial ribs of the core and is machined outside conically in parallel with its recess. It should be noted that the wall of this die is provided with a small thickness, approximately four millimeters, but nevertheless sufficient for the extruded materials to reconstitute in this thickness. In addition, it should be emphasized that, unlike the currently known dies, the extruded materials do not abut 90 on the internal walls of the extrusion head since all these walls are conical in shape, which makes it possible to reduce the pressure. extrusion. In addition, we can thus vary

  the contact border of these materials by adjusting the pressure in the extruders.

  Furthermore, to facilitate the production of this extrusion head, the inventor has devised a manufacturing process which consists in producing the diffuser, the core and the die in the form of parts of revolution which can be produced in series, therefore inexpensive. , only the envelope 40 being provided as a fur to be adjusted to the outside diameters

2598652-

  of the diffuser and of the die with respect to the bore of the flange for fixing the extrusion head. In particular, to machine the ribbing and the grooving of the core, the inventor has designed a molded copper electrode which is adapted to be applied to the blank of the core then in the form of a part of revolution.

  Other characteristics of the present invention will appear from the following description of an embodiment, given as

  non-limiting example, of an extrusion machine according to the invention, designed to simultaneously extrude three continuous coating materials 10 from an insert and shown schematically in the accompanying drawings, in which: - the figure 1 is an overall sectional view of an extrusion machine according to the invention; - Figure 2 is a perspective view in section of the dis15 tributor ring; - Figure 3 is a sectional view of the bias perforations of the distributor ring of Figure 2; - Figure 4 is a perspective view of a closure tip of a bias perforation of the distributor ring; - Figure 5 is a perspective view of a material retainer for the annular grooves of the distributor ring; - Figure 6 is a view of the distributor ring from the side of its face B; - - Figure 7 is a view of the base face A of the frustoconical core 25 of the connecting head, this face being adjacent to the face B of the distributor ring; - Figure 8 is a sectional view of the extrusion head; - Figure 9 is an elevational view, partially in section, of the diffuser; - Figure 10 is a view shown in Figure 9; - Figure 11 is an extrusion view; Figure 12 is a view 35 before the passage of the profile - Figure 13 is a view of the electrode used for machining - Figure 14 is a view

che Fl.

  front, along arrow F, of the flat diffuser in perspective of the core of the head

  in section of the die proper, and the insert is not produced; in elevation, partially in section, of the core of the extrusion head; from below the electrode following the fle-

  As shown in FIG. 1, the machine for the simultaneous extrusion of three materials represented is constituted by three extruding screws 1,2,3 incorporated in the same block 4 and emerging, by a respective orifice 1 ′, 2 ′, 3 ′, in a connection head 5 having three pipes 6,7,8, each of which is in correspondence with one of the orifices, and axially hollowed out for the passage of an insert, this connection head supplying, via a ring perforated distributor 9, an extrusion enclosure 10 with controlled veins carrying at its outlet an extrusion head 11 consisting of a frustoconical fur or envelope 12 housing, from its inlet to its outlet, a frustoconical diffuser 13 ribbed ra10 dialement externally, in which each groove between two radial ribs corresponds to an orifice in the extrusion enclosure 10, a frustoconical core 13a ribbed and grooved radially externally so that its ribs and grooves correspond to those of the diffuser 13, a frustoconical die 13b internally hollowed out conically in correspondence with the conicity of the ribs and radial grooves of the core 13a, this die obviously comprising a passage cut out in the shape of the

desired profile.

  The extruding screws 1,2,3 are housed in bores of the block 4 which are parallel to each other and juxtaposed. This block 4 comprises internal canalizations 20 adapted to circulate the water and the steam coming from the hydraulic motors for rotating the extruding screws. The connection head 5 is integral with the block 4 and houses a frustoconical core 15, axially bored and provided with the three external pipes 6, 7, 8 in the form of helical grooves opening into its base 16 by segmental annular orifices 25, 18 , 19 (as can best be seen in FIG. 7) against the distributor ring 9, these annular orifices being distributed concentrically according to different diameters and in order to have no connection between them. This core 15 further comprises, at its

  top a thread allowing the screwing of a fixing nut 20.

  As shown in particular in Figures 2, 3 and 6, the distributor ring 9 is in the form of a cylindrical ring of the same diameter as the base of the core 15 and comprising a central bore 21 for insert passage. This distributor ring 9 has, on its face B adjacent to the base of the core 15, annular grooves 22, 23, 24, formed in correspondence and with the same diameters as the segment annular orifices 17, 18, 19. These annular grooves further comprise biased perforations 25, 26, 27 opening into a respective common orifice 28 on the opposite face C of the distributor ring, these common orifices 28 being located in correspondence with the intake orifices of the 'enclosure 40 10. The biased perforations 25,26,27 are, moreover, milled to accept accommodating closure points 29 (FIG. 4) and the annular grooves 22,23,24 are adapted to insert retainers 30 (Figure 5) of material according to the desired distribution in each groove of each material supplied to the enclosure according to the determined coating of the insert.

  We will not describe here the constitution of the extrusion enclosure with controlled veins, since it is described in detail, among others, in the aforementioned European patent.

  The extrusion head 11, shown as a whole in FIG. 8, consists, as indicated above, of a frustoconical casing 12 incorporating a frustoconical diffuser 13 ribbed and grooved radially, a frustoconical core 13a ribbed and grooved also radially in correspondence with the diffuser and a conically hollow die 13b in which the ribs of the core abut. The casing 12 of frustoconical for15 me is adapted to be housed in the mounting flange 12a

  of the extrusion head and is tapered convergently towards its outlet to maintain the stacking of the diffuser, of the core and of the die, as well as a sealing ring 13c placed at the rear of the diffuser and having a corresponding bore to the circumscribed circle of the orifices 20 28a of the extrusion enclosure, the rear face of this ring 13c being placed on the front or outlet face of this enclosure.

  For its part, the frustoconical diffuser (represented in FIGS. 9 and 10) is constituted in a single block where the radial ribs 31, of frustoconical external shape with converging conicity, form grooves 32 between them, the bottom of which is with diverging conicity in the direction of their exit, the bottoms 32a at the inlet being curved less than the diameter of the inscribed circle of the outlet orifices 28a of the extrusion enclosure with controlled veins and these bottoms, on the outlet side, corresponding to the outside diameter of the core frustoconical 13a. Note that one of the ribs 30 31a of this diffuser is thicker than the others and has a channel

internal air intake 31b.

  Furthermore, this frustoconical core (shown in FIG. 11) also consists of a single block o the radial ribs 33 and the bottom of the grooves 34 has a converging taper towards their outlet 35 on the side of the die, this bottom of each groove being rounded so that a single generator touches the bottom of the die. As far as it is concerned, the wall 35 of this die (represented in FIG. 12) is hollowed conically in correspondence with the conicity of the radial ribs of the core

  13a and is machined outside conically in parallel with its recess

  is lying. It should be noted that the wall 35 of this die is expected to be small

7 2598652

  thickness, about four millimeters, but still sufficient for

  the extruded materials are reconstituted in this thickness.

  As mentioned above, the inventor uses for the machining of the core 13a, taken from a part of revolution, an elec5 molded copper electrode shown in FIGS. 13 and 14. This electrode has radial ribs 36 intended to dig the grooves 34, leaving between them the radial ribs 33 corresponding to its

grooves 37.

Claims (11)

R E V E N D I C A T I O N S   1.- Machine for the simultaneous extrusion of several materials, in particular suitable for coating a profiled insert, characterized in that it is constituted by several extruding screws (1,2,3) incorporated in the same block (4 ), each supplied from a particular hopper 5 and opening, through a respective orifice (1 ′, 2 ′, 3 ′), into a connection head (5) having a particular channel (6,7,8) for each beaded material and axially hollowed out for the passage of an insert, this connection head (5) supplying, via a distributor ring (9) perforated and grooved concentrically along the channels of the latter, an enclosure d extrusion (10) with controlled veins known in the art, carrying at its outlet an extrusion head (11), with a passage reserved for the insert, consisting of a frustoconical fur or envelope (12) housing, from its inlet at its outlet, a frustoconical diffuser (13) ribbed radially on the outside, in which each groove 15 between two radial ribs corresponds to an orifice in the extrusion enclosure (10), a frustoconical core (13a) ribbed and grooved radially externally so that its ribs and grooves correspond to those of the diffuser (13), a frustoconical die (13b) hollowed out internally in a conical manner in correspondence with the taper of the ribs and 20 radial grooves of the core (13a), this die obviously comprising a   passage cut to the shape of the desired profile.   2.- extrusion machine according to claim 1, characterized in that the extruding screws (1,2,3) are housed in bores of the block (4) parallel to each other and juxtaposed, this block being provided with 25 pipes internal (14) surrounding these screws like a radiator and circulating water and steam from the hydraulic motors of rotation of these screws.   3.- extrusion machine according to claim 1, characterized in that the connecting head (5) is integral with the block (4) of the extruders and houses a core (15) of frustoconical shape axially bored to provide the passage of the insert and provided with external grooves   (6,7,8) of substantially helical shape, opening by segmental annular orifices (17,18,19) against the distributor ring (9), in a number equal to that of the screws and each originating at the level of the exit port of a plodder.   4.- extrusion machine according to claim 3, characterized in that the frustoconical core (15) of the connecting head (5) is fixed, has a base in which are formed the annular orifices (17,18,19 ), at the outlet of the outer grooves, according to different diameters to avoid any connection between them, has a threaded top for screwing its nut (20) for fixing in the block (4)   and is positioned normal to the extruders (1,2,3) in line.   5.- extrusion machine according to claim 1, characterized in that 1 distributor ring (9) is in the form of a cylindrical ring, of the same diameter as that of the base of the core (15) of the head link (5), bored axially by an orifice (21) for inserting the passage in correspondence with that of this core and provided, on its face 10 adjacent thereto, with annular grooves (22, 23, 24) provided for same diameters as those of the segmental annular orifices (17,18,19) of the base of this core, these annular grooves being provided with biased perforations (25, 26,27) opening into orifices (28) provided in the opposite face of   this ring in correspondence with the inlet orifices of the enclosure 15 (10) with controlled veins.   6.- extrusion machine according to claim 5, characterized in that the biased perforations (25,26,27) in the annular grooves of the distributor ring are milled to accept closure points (29) depending of annular grooves used in the re20 partition of the extruded materials, these grooves being themselves designed to receive retainers (30) of material distributed according to the delimitation of the groove segments chosen for supplying the orifices enclosure admission (10).   7. Extrusion machine according to claim 1, characterized in that the casing (12) of the extrusion head (11) is adapted to be housed in the fixing flange (12a) of the head d extrusion and is conically bored convergently towards its outlet to maintain the stacking of the diffuser, of the core and of the die, as well as a obturating ring (13c) placed at the rear of the diffuser and having a bore cor30 corresponding to the circumscribed circle of the orifices (28a) of the extrusion chamber, the rear face of this ring (13c) being pressed against the face   before or leaving this enclosure.   8.- extrusion machine according to claim 1, characterized in that the frustoconical diffuser is formed in a single block where the radial ribs (31), of frustoconical external shape with converging taper, form grooves between them (32 ) the bottom of which is with divergent conicity in the direction of their exit, the bottoms (32a) at the inlet being curved less than the diameter of the inscribed circle of the outlet orifices (28a) of the extrusion enclosure with controlled veins and these 40 bottoms, on the outlet side, corresponding to the outside diameter of the core frustoconical (13a).   9.- extrusion machine according to claim 1, characterized in that the frustoconical core also consists of a single block o the radial ribs (33) and the bottom of the grooves (34) is co5 nicity converging towards their outlet on the side of the die, this bottom of each groove being rounded so that a single generator touches the bottom of the sector.   10.- extrusion machine according to claim 1, characterized in that the wall (35) of the die (13b) is hollowed conically 10 in correspondence with the taper of the radial ribs of the core (13a), machined conically to l outside in parallel with its recess and planned thin, about four millimeters, but still sufficient   so that the extruded materials are reconstituted in this thickness.   11.- Method of manufacturing an extrusion head according to re15 vendications 7, 8, 9, 10, characterized in that it consists in machining the diffuser (13), the core (13a) and the die ( 13b) from blanks in the form of parts of revolution, using copper electrodes   molded conformed in the form of these diffuser, core and die.